The present disclosure generally relates to subterranean formation operations and, more particularly, to the selection of optimal surfactants for performing surfactant flooding enhanced oil recovery operations.
Subterranean wells (e.g., hydrocarbon producing wells) are often stimulated by hydraulic fracturing treatments. In traditional hydraulic fracturing treatments, a treatment fluid, which may also function simultaneously or subsequently as a carrier fluid, is pumped into a portion of a subterranean formation (which may also be referred to herein simply as “formation”) at a rate and pressure sufficient to break down the formation and create one or more fractures therein. Typically, particulate solids, such as graded sand, are suspended in a portion of the treatment fluid or suspended in a subsequent fluid, and deposited into the fractures. These particulate solids, known as “proppant particulates” (which may also be referred to herein simply as “proppant”) gather in a fracture, forming a “proppant pack,” that serves to prevent the fractures from fully closing once the hydraulic pressure is removed. Conductive paths through which produced fluids from the formation may flow are formed between the interstitial spaces of the proppant particulates forming the proppant pack.
After a hydraulic fracturing treatment (or other stimulation treatment), oil recovery may commence. Oil recovery is typically separated into three stages: primary oil recovery, secondary oil recovery, and tertiary oil recovery. During primary oil recovery, the natural pressures of the reservoir may be used to push hydrocarbons to the surface, which may allow for about 5-10% of the hydrocarbons in the formation to be recovered. During secondary and tertiary oil recovery, substances, such as water, gas, or other fluids or chemicals, may be pushed therein to drive out the remaining hydrocarbons that could not be recovered during primary oil recovery. During any one of these three stages (i.e., the productive life of a formation), an enhanced oil recovery (EOR) technique may be employed to alter the original properties of the oil and increase production. EOR techniques may be used to restore formation pressure, improve oil displacement or fluid flow from the formation, and the like. The primary types of EOR techniques are chemical flooding, miscible displacement, and thermal recovery.